1. FIELD OF THE INVENTION
This invention relates to a ship loading system for bulk cargo, particularly cargo which is suitable for continuous conveyance by endless conveyors, e.g. belts. Examples of such cargoes are coal and iron ore either in the form of course or fine granules or in the form of pellets.
2. DESCRIPTION OF THE PRIOR ART
Ship loading systems for loading bulk cargo into large ocean-going vessels are known in which there is a single shiploader which is movable along substantially the whole length of the ship's berth, there being a single conveyor supplying the cargo to the shiploader and a tripper in the conveyor for delivery to the shiploader. The tripper moves with the shiploader. See for instance U.S. Pat. No. 3,388,818 and "The Dock and Harbour Authority", Vol. 53, page 255 (November 1972). The disadvantage of such systems is that delivery must be stopped completely when the shiploader is moved from one hold to another and that if the shiploader breaks down, loading is delayed indefinitely.
Other systems are known, in which two shiploaders are provided, both being capable of slewing so as to reach a number of hatches in the ship, but not being bodily shiftable along the ship's berth. An example is the plant installed at the Port of Tubarao, Brazil, described for example in "Fordern und Heben" 23 (1973) No. 7 pages 367, 368 and 24 (1974) No. 13, pages 1221 to 1224. In this case an approach conveyor delivers the cargo onto two separate parallel conveyors which deliver it respectively to the two shiploaders. Disadvantages of this plant are the very large size of the slewing shiploaders, the inability of one of the shiploaders to load the whole ship (without movement of the ship) if the other shiploader breaks down or is under construction, and the number of conveyors required together with the fact that the system is not symmetrical about a longitudinal axis, so that loading on both sides of a quay is not possible.
The reference in "The Dock and Harbour Authority" given above also refers to the possibility of using two slewing loaders or two travelling loaders, though the latter alternative is discounted on economic grounds.